This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/337,020, filed Dec. 3, 2001, incorporated herein by reference.
The instant invention relates to settings for gemstones, such as box-type gemstone settings, and more particularly relates to box-type gemstone settings that are linked together form a continuous jewelry chain and typically sold in continuous spool form. Even more specifically, the present invention is related to the manufacture of rhinestone jewelry chain.
In the prior art, a typical box-type setting for a gemstone includes four prongs for holding the stone in the setting (See FIG. 1). There is typically a prong located at each corner of the setting, and each prong is bent over the top of the stone to retain the stone within the setting. Although this arrangement has been used for many years, one particular issue continues to create a problem with the use of this type of setting, namely, that the prongs still catch on various loose-knit clothing fabrics. Even though the prongs are bent over on top of the stone as described above, the terminal ends of the prongs are still exposed and project slightly from the top of the stone. This slight projection causes the prongs to occasionally to catch on, and pull, various types of loose-knit fabrics, such as sweaters. Further, if the prongs are caught or snagged, they may bend away from the stone, thus no longer retaining the stone and causing the stone to fall out of the setting.
Other types of prior art settings include a concealed-type setting where the stone is grooved along opposing facets on the underside of the gemstone. While this type of setting prevents any exposed prongs from snagging the clothing of the wearer, it requires that the stones be specially manufactured. Furthermore, this type of grooving requires additional labor in the cutting of the gemstone and is only suitable for square or rectangular gemstones.
Another type of gemstone setting is referred to a bezel setting where the entire edge of the stone is retained by bending the edge of the setting over the perimeter of the top of the gemstone. This is a very effective method of retaining a gemstone within a setting and it provides a great deal of protection for the stone. The drawback to this type of setting is that it conceals both the edge and a portion of the top face of the stone. By concealing the stone in this manner, it causes the stone to appear smaller and prevents some of the light that enters the stone from reflecting back out.
Yet another type of setting in the prior art is a two-piece setting. A first piece of the setting retains two opposing edges of the gemstone and is placed within a second piece that retains the other two sides of the stone and also provides the linking elements. This type of setting has the same drawbacks as the bezel setting described above, in addition to having two pieces that add to the complexity of forming the setting and the labor required for assembly.
The present invention provides an improved setting for a gemstone that overcomes the deficiencies noted above. In the present invention, the conventional gemstone setting method of using four prongs to retain the stone is replaced using a pair of arcuate loops that form curved bars which are then bent over on top of the stone.
The first step in forming the gemstone setting of the present invention begins with forming a blank. The blank is stamped from a flat piece of sheet metal and has a main body, four tabs and two crescent shaped loops that extend outwardly from the opposing sides of the main body. The tabs are bent upwardly relative to the ends of the main body and the ends of the main body are bent upwardly, whereby the ends of the main body form two sides of a box setting and the tabs form the remaining two sides to complete the box. The crescent loops extend above the sides of the box.
Once the box is formed, a gemstone is set into the open top of the box and the crescent loops are bent down over the top of the gemstone to retain the stone in the setting. In this manner, the crescent loops retain the gemstone and serve the same function that the prongs served in the prior art. However, since the present invention does not use prongs, there are no exposed terminal ends to snag loose-knit fabrics. Further, since there are no exposed terminal ends of the prongs, it is less likely that the retaining elements of setting will be accidentally bent causing the stone to come loose.
A plurality of box-type settings formed in accordance with the present invention can be connected together using linking elements to create a chain. In this fashion, the manufacturer can produce a continuous chain of set gemstones that can be used by jewelry designers and assemblers for incorporation into finished jewelry articles.
It is therefore an object of the present invention to provide a gemstone setting that has a reduced tendency to snag the garment of the wearer. It is a further object of the present invention to provide a gemstone setting that provides additional security for retaining the gemstone within the setting. It is yet another object of the present invention to provide a setting for a gemstone that is snag free while in turn minimizing the amount of setting material that covers and conceals the gemstone.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.